Thread by @bugcounter

Room temperature thawing of frozen meat is an interesting topic that comes up from time to time. If you check all of the food safety advice websites they will tell you that it is not safe to do this. (1/18)

They will instead recommend that you thaw in the refrigerator, in the microwave, or under running water. (2/18)

See for example: fightbac.org/food-safety-ba… or fsis.usda.gov/wps/wcm/connec… (3/18)

I'm not sure how room temperature thawing got such a bad rap, except perhaps it is guilt by association. (4/18)

We always tell people that foods should not be out of temperature control for more than a couple of hours, so of course to thaw a big piece of frozen raw meat you would need more than two hours. (5/18)

However, if dig into the scientific literature, you will discover that it's actually a little bit more complicated than that. (6/18)

My first awareness that it might be possible to safely thaw frozen meat at room temperature comes from famous food safety curmudgeon Pete Snyder (RIP). (7/18)

See this paper by S.M.Jimenez et al, (last author Pete Snyder) published in Dairy, Food and Environmental Sanitation, Vol. 20, No. 9, Pages 678-683, published in 2000. researchgate.net/publication/28… (8/18)

They showed that "thawing chicken on the counter at ambient temperature (21 °-22°C) within 14 hours or less, to an internal temperature of 4.4°C (3.5 cm within the breast), is a safe procedure, as evidenced by a decline in bacterial population" (9/18)

In a much earlier paper (1968) by Klose, A. A., H. Lineweaver, and H. H. Palmer. "Thawing turkeys at ambient air temperatures." Food Technology 22.10: 1310-1314. (10/18)

The authors note: "An important increase in time between thawing and potential bacterial growth was observed when the bird in its plastic film was enclosed in an insulating double-walled paper bag for thawing." (11/18)

Those same authors go on to say: "The insulation kept the surface temperature low without unduly prolonging thawing time" (12/18)

Our own paper by Mcconnell and Schaffner (pubmed.ncbi.nlm.nih.gov/24988016/) is not on calling of meat, but rather the validation of existing models for the growth of salmonella on ground beef exposed to changing temperature profiles. (13/18)

Our paper shows that the models are generally feel safe for the behavior of Salmonella, which means if we have time and temperature data we can use models to guide our decisions. (14/18)

What really matters thawing of frozen meat is the temperature at the surface of the meat (since that is generally where the meat will be the warmest) (15/18)

Depending upon how the meat is being thawed (See the double paper bag technique from the 1968 paper above), the temperature at the surface may actually remain very close to freezing as the meat thaws. (16/18)

So can you safely thaw meat at room temperature? My answer is yes, but I would encourage you to measure the temperature at the surface throughout the thawing process with a tip sensitive digital thermometer. (17/18)

Remember that once that tip touches the raw meat, it will need to be cleaned and sanitized. As long as the temperature does not rise much above 40°F this is an acceptable practice.
 (18/18)